Straight-bar knitting machine



Feb. 1, 1938. H. w. START ET AL 2,107,221

STRAIGHT BAR KNITTING MACHINE I I Filed May 11, 1957' 2 Sheets-Sheet -1Feb. 1, 1938. H. w. START ET AL 2,107,221

STRAIGHT BAR KNITTING MACHINE Filed May 11, 1937 2 Sheets-Sheet 2 v;) inconsequence the friction between the bar and is adapted to compress thefriction plates in the 50 55 reciprocating slur-cock rail carries adriving F is released. H 55 Patented Feb. 1 1938 UNITED STATES PATENTOFFICE STRAIGHT-BAR KNITTING MACHINE Harry Wilfred Start, Carlton, andErnest Start,

Wilford, England, assignors to George Blackburn and- Sons Limited,Nottingham, England Application May 11, 1937, Serial No. 142,008 InGreat Britain March 10, 1936 6 Claims. (Cl. 66-126) This inventionrelates to straight-bar knitting member which engages with a latch onthe fricmachines such for example as those known as tion box when it isat rest and positively moves Cottons, in which the thread carriers aredisit for a short distance. The latch which is posed on longitudinalbars which are reciprolocked by a tumbler during this initial movement 5cated in the direction of their length, and it reis then released fromthe driving member While 5 fers to improvements in the means which arethe friction plates in the friction box are siemployed transmittinglongitudinal reciprocatmultaneously pressed down on the reciprocatinging movements to the said bars. friction bar, so that the remainder ofthe move- The amplitude of movement of these thread ment is frictionallyeffected by the said bar. On

10 carrier bars has to be varied from time to time the completion of themovement the friction is 10 in order to vary the width of the knittedfabric released, and the return movement is started by produced, and forthis reason the usual arrangethe positive arrangement again. mentadopted is to drive these bars through the A brake is provided to holdthe friction box agency of one or more friction boxes disposed on whenit is released from the friction bar and is friction bars, and checkthem at the required at rest, in order to prevent it from creeping out15 points by, means of adjustable end stops. The of its proper positionduring the initial moveobject of the present invention is to provideposiments of the friction bar.

tive means for imparting the initial movements The invention will now bemore particularly to the thread carrier bars, and frictional meansdescribed with reference to the accompanying for completing suchmovements. With this sysdrawings, in which 20 tem higher speeds can beattained without risk, Fig. 1 is a vertical cross section, and

and the friction can be reduced, so that less Fig. 2 a front elevation,and

power is wasted in driving the machine and less Fig. 3 a plan of threadcarrier driving mechwear is set up. anism constructed according to ourinvention.

This improved result is due to the fact that Fig. 4 is a cross sectionof a knitting machine 25 more power is required to overcome the inertiaof to which the invention is applied.

the said carriers bars when they are at rest than Like letters indicatelike parts throughout the is required to keep them moving, and byproviddrawings. ing positive means for starting the movements, InCarrying out t invention, the friction 100K a moderate amount offrictional contact is only A (see Figs. 1 and 2) which is mounted on the30 necessary to complete such movements, and the o t d y reciprocatingfriction bar is frictional resistance that is met with when the fittedon its underside with a latch B which carrier bars are stopped isconsiderably reduced. is pivoted to the friction bOX at B1 and is p Inthe usual arrangement, the friction box is vided at its free end with anose B This nose 5 mounted on a longitudinal friction bar which is B isbevelled on both sides, and a bracket D on disposed just above theslur-cock rail, and this the longitudinally reciprocating slur cock railE, friction bar is connected to and receives positive is fitted with adrivin member D1 which is reciprocating movements from the said rail.The bevelled at each end and is adapted to engage thread carrier bar isconnected to the friction with the nose B of the latch B, when the rail40 box, and it will be understood, that when the E is moving in eitherdirection. When the latch 40 thread carrier bar is stopped, the frictionbox B is looked as will be hereinafter described, the will stop, whilethe friction bar on which it is driving member D will drive the frictionbox A, disposed will continue its movement, and conbut will release itas soon as the latch B is resequently the frictional resistance set upbetween leased.

the friction box and the bar has to be overcome. The friction set upbetween the friction box A 45 'It will also be understood that undernormal and the friction bar C in the present case isconcircumstances,the frictional grip of the box on trolled by the action of a cam lever Fwhich. is the bar must be adjusted so that it will promptly pivoted inthe top of the box. This cam lever start the thread carrier bar fromrest, and that F which is hereinafter termed the friction lever,

the friction box must be very considerable, and friction box on to thefriction bar C, when its that it acts like an efficient brake on themovfree end is depressed, and thuscause the box ing friction bar whenthe. friction box is stopped. A to grip the friction bar C. This grip isagain According to this invention a bracket on the relieved when thefree end of the friction lever Above the friction box A is a bar G whichis disposed parallel to the friction bar 0. This bar G is carried in thefree ends of two arms G secured on a rocking shaft G which latter isdisposed parallel to the friction bar C in bearings G secured on a fixedlongitudinal shaft H.

The rocking shaft G is provided with another arm G which has its freeend connected by a connecting rod G to a lever G (see Fig. 3) which isactuated by a cam G7 on the main cam shaft G of the machine. This cam Gis adapted to depress the bar G which is hereinafter termed the presserbar, down on to the free end of the friction lever F on the friction boxA, and the friction grip when applied can be maintained as long as isrequired even when the friction box is reciprocating, as the presser barG is adapted to maintain its pressure on the friction lever F underthese circumstances.

Pivoted on the friction box A between the free end of the latch B andthe free end of the friction lever F, is a tumbler J, and when thistumbler is in its normal position, in which it is shown in Fig. 2, itslower end engages with an upward extension of and locks the latch B,Whilst its upper end is in the path of the free end of the frictionlever F,so that when this lever F is depressed, it engages with andmoves the lower end of the tumbler J clear of and releases the latch B.It thus follows that the latch B is released and the positive connectionbroken as soon as the friction lever F is depressed and the friction boxA is gripped to the friction bar C. The tumbler J is returned to itsnormal position again as soon as it is released by means of a spring JThe action of the arrangement described is as follows:-

At the commencement of each movement, the driving member D on thebracket D on the slur cock rail E, engages with the nose B of the latchB on the underside of the friction box A, and effects the first half ofthe movement by a positive connection. As soon as the friction box A hasmoved to the half way point, the friction lever F is depressed by thebar G and the tumbler J turned so as to release the latch B and destroythe positive connection. The remaining half of the movement is theneffected by the frictional grip of the box A on the friction bar C, sothat when the friction box A is stopped, the driving member D which hascontinued to move with the friction box A, now moves past the nose B ofthe latch B, and is ready to start the return movement by a positiveconnection with the latch B again which is again locked by the tumbler Jwhen the presser bar G is raised at the termination of each movement.

With this arrangement, not only is the thread carrier bar A (shown inFig. 4) started promptly from rest without fail, but the frictionrequired between the friction bar E and the friction box A can beconsiderably reduced, so that the resistance set up when one is stoppedwithout the other is also reduced. The prompt starting of the threadcarrier bars A is specially important when making plated goods, as theplated thread carriers then only have a very short lead in advance ofthe slur-cocks, and the loss of any of this results in the sinkersstriking the thread carriers and causing serious damage.

The thread carrier bar A is connected to the friction box Ain the usualmanner by an arm A which is pivoted in the box A and has a slide A atits end which can be moved into and out of engagement with the threadcarrier bar A It has been found that the friction box A has a tendencyto move with the friction bar 0, before the driving member D reaches it,and in order to obviate this risk, a brake is provided to hold the boxuntil such time as the driving member D engages with the latch Btherein, and the following arrangement is adopted for this purpose.

A toothed rack K on the friction box A engages with a toothed wheel K onthe rear end of an axle K which is mounted in a bearing K secured to thefixed shaft H previously referred to, and the rear end of the axle isfitted with a brake drum K in which are disposed expanding brake shoesof the usual type. At the front of the brake drum K is a plate K whichis mounted on the axle K and this plate is prevented from turning bymeans of an extension plate K which has a forked lower end which engageswith a collar K on a shaft K Mounted in the fixed plate K is an axle Lwith a brake shoe expanding cam on its inner end and an arm L on itsouter end, and the brake is applied and removed by adjusting this arm LThis arm L is connected as will be hereinafter described to a lever Mwhich is pivoted at M to the front of the friction box A and is providedat its free end with an antifriction roller M which is disposed near thenose B on the latch B. The bracket'D previously described, is providedwith cam member D which engages with the roller M on and raises the freeend of the lever M, at the same time as the driving member D engageswith the nose B of the latch, and this movement of the lever M istransmitted to the brake arm L and serves to release the brake at thesame time as the driving member D engages with the latch B in thefriction box A.

The lever M is connected to the brake arm L by the followingarrangement. At the front of the friction box A is a longitudinal bar N,which is carried in the free ends of arms N on a rocking shaft N whichis carried in bearings N secured to the fixed shaft H, and when thelever M is raised as previously described, a roller M thereon engageswith the underside of and raises this bar N and rocks the shaft N andanother arm- N on the latter is connected by a link N to the brake leverL and releases the brake. When the brake lever L is released, the brakeis again applied by the action of a spring N one end of which isconnected to the arm N on the shaft and the other end to a hook member Nsecured to the brake drum plate K A further arrangement is provided toinsure the release of the brake when the friction lever F on thefriction box A is depressed by the presser bar G. This arrangementconsists of an arm 0 on the presser bar shaft G which engages with anarm 0 on the rocking shaft N What we claim is:

1. In straight-bar knitting machine thread carrier driving mechanism, alongitudinally reciprocating friction bar, a friction box mountedthereon, a thread carrier bar connected to the friction box, a pivotedlatch on the friction box, a tumbler for locking the latch, a drivingmember carried on the reciprocating slur cock rail which is adapted toengage with the latch on the friction box and give the latter a positivestarting movement firstin one direction and then in the other, and meansfor releasing the latch and destroying the positive driving connection,substantially as described.

2. In straight-bar knitting machine thread car- 5 rier drivingmechanism, a longitudinally reciprocating friction bar, a friction boxmounted thereon, a thread carrier bar connected to the friction box, apivoted latch on the friction box, a tumbler for locking the latch, adriving member carried on the reciprocating slur cock rail which isadapted to engage with the latch on the friction box and give the lattera positive starting movement first in one direction and then in theother, a friction lever on the friction box for applying the frictionalgrip to the friction bar, means for depressing this lever, and a latchlooking tumbler with a part which is engaged by the friction lever whendepressed whereby the said tumbler is at the same time turned so as torelease the latch, substantially as described.

3. In straight-bar knitting machine thread carrier driving mechanism, alongitudinally reciprocating friction bar, a friction box mountedthereon, a thread carrier bar connected to the friction box, a pivotedlatch on the friction box formed with a nose, a tumbler for locking thelatch, a driving member carried on the reciprocating slur cock railwhich is adapted to engage with the latch on the friction box and givethe latter a positive starting movement first in one direction and thenin the other, a friction applying lever on the friction box, alongitudinal bar for depressing the friction lever carried by arms on arocking shaft which is connected to and actuated by a cam on a runningshaft, and a latch locking tumbler with a part which is engaged by thefriction lever when it is depressed whereby the said tumbler is at thesame time turned so as to release the latch, substantially as described.

4. In straight-bar knitting machine thread carrier driving mechanism, alongitudinally reciprocating friction bar, a friction box mountedthereon, a thread carrier bar connected to the friction box, a pivotedlatch on the friction box formed with a nose, at tumbler for locking thelatch, a driving member carried on the reciprocating slur cock railwhich is adapted to engage with the nose of the latch on the frictionbox and give the latter a positive starting movement first in onedirection and then in the other, means for releasing the latch so as todestroy the positive driving connection and simultaneously applying thefrictional grip on the friction bar, a toothed rack on the friction box,an axle with a toothed pinion in engagement with the rack, a brake drumon the axle fitted with brake shoes which are expanded by a springactuated cam, and means for releasing the brake at the commencement ofeach movement of the friction box, substantially as described.

5. In straight-bar knitting machine thread carrier driving mechanism, alongitudinally reciprocating friction bar, a friction box mountedthereon, a thread carrier bar connected to the friction box, a pivotedlatch on the friction box with a nose, a tumbler for locking the latchand. a driving member carried on the reciprocating slur cock rail whichis adapted to engage with the nose of the latch on the friction box andgive the latter a positive starting movement first in one direction andthen in the other, means for releasing the latch so as to destroy thepositive driving connection and simultaneously applying the frictionalgrip on the friction bar, a toothed rack on the friction box, an axlewith a toothed pinion in engagement with the rack, a brake drum on theaxle fitted With brake shoes which are expanded by a lever, a springconnected to this lever which holds the brake on, a lever on thefriction box which is tripped by a cam member on the slur-cock rail andmeans for connecting the lever on the friction box to the brake lever sothat the brake is released at the commencement of each movement of thefriction box, substantially as described.

6. In straight-bar knitting machine thread carrier driving mechanism, alongitudinally reciprocating friction bar, a friction box mountedthereon, a thread carrier bar connected to the friction box, a latchpivoted on the friction box with a nose, at tumbler for locking thelatch, and a driving member carried on the reciprocating slur-cock railwhich is adapted to engage with the nose of the latch on the frictionbox and give the latter a positive starting movement first in onedirection and then in the other, a friction lever on the friction box, alongitudinal bar for depressing the friction lever carried by arms on arocking shaft, a cam on a running shaft for actuating the rocking shaft,brake mechanism, an arm on the rocking shaft which is connected to thebrake mechanism, a latch locking tumbler on the friction box which isengaged by the friction lever when it is depressed whereby the saidtumbler is turned to release the latch at the same time as thefrictional grip is applied to the friction bar, substantially asdescribed.

HARRY WILFRED START. ERNEST START.

